1 /*- 2 * Copyright (c) 2013 The FreeBSD Foundation 3 * 4 * This software was developed by Benno Rice under sponsorship from 5 * the FreeBSD Foundation. 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28 #include <sys/param.h> 29 30 #include <stand.h> 31 #include <bootstrap.h> 32 33 #include <efi.h> 34 #include <efilib.h> 35 36 #include "loader_efi.h" 37 38 #define M(x) ((x) * 1024 * 1024) 39 #define G(x) (1UL * (x) * 1024 * 1024 * 1024) 40 41 #if defined(__amd64__) 42 #include <machine/cpufunc.h> 43 #include <machine/specialreg.h> 44 #include <machine/vmparam.h> 45 46 /* 47 * The code is excerpted from sys/x86/x86/identcpu.c: identify_cpu(), 48 * identify_hypervisor(), and dev/hyperv/vmbus/hyperv.c: hyperv_identify(). 49 */ 50 #define CPUID_LEAF_HV_MAXLEAF 0x40000000 51 #define CPUID_LEAF_HV_INTERFACE 0x40000001 52 #define CPUID_LEAF_HV_FEATURES 0x40000003 53 #define CPUID_LEAF_HV_LIMITS 0x40000005 54 #define CPUID_HV_IFACE_HYPERV 0x31237648 /* HV#1 */ 55 #define CPUID_HV_MSR_TIME_REFCNT 0x0002 /* MSR_HV_TIME_REF_COUNT */ 56 #define CPUID_HV_MSR_HYPERCALL 0x0020 57 58 static int 59 running_on_hyperv(void) 60 { 61 char hv_vendor[16]; 62 uint32_t regs[4]; 63 64 do_cpuid(1, regs); 65 if ((regs[2] & CPUID2_HV) == 0) 66 return (0); 67 68 do_cpuid(CPUID_LEAF_HV_MAXLEAF, regs); 69 if (regs[0] < CPUID_LEAF_HV_LIMITS) 70 return (0); 71 72 ((uint32_t *)&hv_vendor)[0] = regs[1]; 73 ((uint32_t *)&hv_vendor)[1] = regs[2]; 74 ((uint32_t *)&hv_vendor)[2] = regs[3]; 75 hv_vendor[12] = '\0'; 76 if (strcmp(hv_vendor, "Microsoft Hv") != 0) 77 return (0); 78 79 do_cpuid(CPUID_LEAF_HV_INTERFACE, regs); 80 if (regs[0] != CPUID_HV_IFACE_HYPERV) 81 return (0); 82 83 do_cpuid(CPUID_LEAF_HV_FEATURES, regs); 84 if ((regs[0] & CPUID_HV_MSR_HYPERCALL) == 0) 85 return (0); 86 if ((regs[0] & CPUID_HV_MSR_TIME_REFCNT) == 0) 87 return (0); 88 89 return (1); 90 } 91 92 static void 93 efi_verify_staging_size(unsigned long *nr_pages) 94 { 95 UINTN sz; 96 EFI_MEMORY_DESCRIPTOR *map = NULL, *p; 97 EFI_PHYSICAL_ADDRESS start, end; 98 UINTN key, dsz; 99 UINT32 dver; 100 EFI_STATUS status; 101 int i, ndesc; 102 unsigned long available_pages = 0; 103 104 sz = 0; 105 106 for (;;) { 107 status = BS->GetMemoryMap(&sz, map, &key, &dsz, &dver); 108 if (!EFI_ERROR(status)) 109 break; 110 111 if (status != EFI_BUFFER_TOO_SMALL) { 112 printf("Can't read memory map: %lu\n", 113 EFI_ERROR_CODE(status)); 114 goto out; 115 } 116 117 free(map); 118 119 /* Allocate 10 descriptors more than the size reported, 120 * to allow for any fragmentation caused by calling 121 * malloc */ 122 map = malloc(sz + (10 * dsz)); 123 if (map == NULL) { 124 printf("Unable to allocate memory\n"); 125 goto out; 126 } 127 } 128 129 ndesc = sz / dsz; 130 for (i = 0, p = map; i < ndesc; 131 i++, p = NextMemoryDescriptor(p, dsz)) { 132 start = p->PhysicalStart; 133 end = start + p->NumberOfPages * EFI_PAGE_SIZE; 134 135 if (KERNLOAD < start || KERNLOAD >= end) 136 continue; 137 138 available_pages = p->NumberOfPages - 139 ((KERNLOAD - start) >> EFI_PAGE_SHIFT); 140 break; 141 } 142 143 if (available_pages == 0) { 144 printf("Can't find valid memory map for staging area!\n"); 145 goto out; 146 } 147 148 i++; 149 p = NextMemoryDescriptor(p, dsz); 150 151 for ( ; i < ndesc; 152 i++, p = NextMemoryDescriptor(p, dsz)) { 153 if (p->Type != EfiConventionalMemory && 154 p->Type != EfiLoaderData) 155 break; 156 157 if (p->PhysicalStart != end) 158 break; 159 160 end = p->PhysicalStart + p->NumberOfPages * EFI_PAGE_SIZE; 161 162 available_pages += p->NumberOfPages; 163 } 164 165 if (*nr_pages > available_pages) { 166 printf("Staging area's size is reduced: %ld -> %ld!\n", 167 *nr_pages, available_pages); 168 *nr_pages = available_pages; 169 } 170 out: 171 free(map); 172 } 173 #endif /* __amd64__ */ 174 175 #if defined(__arm__) 176 #define DEFAULT_EFI_STAGING_SIZE 32 177 #else 178 #define DEFAULT_EFI_STAGING_SIZE 64 179 #endif 180 #ifndef EFI_STAGING_SIZE 181 #define EFI_STAGING_SIZE DEFAULT_EFI_STAGING_SIZE 182 #endif 183 184 #if defined(__aarch64__) || defined(__amd64__) || defined(__arm__) || \ 185 defined(__riscv) 186 #define EFI_STAGING_2M_ALIGN 1 187 #else 188 #define EFI_STAGING_2M_ALIGN 0 189 #endif 190 191 #if defined(__amd64__) 192 #define EFI_STAGING_SLOP M(8) 193 #else 194 #define EFI_STAGING_SLOP 0 195 #endif 196 197 static u_long staging_slop = EFI_STAGING_SLOP; 198 199 EFI_PHYSICAL_ADDRESS staging, staging_end, staging_base; 200 bool stage_offset_set = false; 201 ssize_t stage_offset; 202 203 static void 204 efi_copy_free(void) 205 { 206 BS->FreePages(staging_base, (staging_end - staging_base) / 207 EFI_PAGE_SIZE); 208 stage_offset_set = false; 209 stage_offset = 0; 210 } 211 212 #ifdef __amd64__ 213 int copy_staging = COPY_STAGING_AUTO; 214 215 static int 216 command_copy_staging(int argc, char *argv[]) 217 { 218 static const char *const mode[3] = { 219 [COPY_STAGING_ENABLE] = "enable", 220 [COPY_STAGING_DISABLE] = "disable", 221 [COPY_STAGING_AUTO] = "auto", 222 }; 223 int prev, res; 224 225 res = CMD_OK; 226 if (argc > 2) { 227 res = CMD_ERROR; 228 } else if (argc == 2) { 229 prev = copy_staging; 230 if (strcmp(argv[1], "enable") == 0) 231 copy_staging = COPY_STAGING_ENABLE; 232 else if (strcmp(argv[1], "disable") == 0) 233 copy_staging = COPY_STAGING_DISABLE; 234 else if (strcmp(argv[1], "auto") == 0) 235 copy_staging = COPY_STAGING_AUTO; 236 else { 237 printf("usage: copy_staging enable|disable|auto\n"); 238 res = CMD_ERROR; 239 } 240 if (res == CMD_OK && prev != copy_staging) { 241 printf("changed copy_staging, unloading kernel\n"); 242 unload(); 243 efi_copy_free(); 244 efi_copy_init(); 245 } 246 } else { 247 printf("copy staging: %s\n", mode[copy_staging]); 248 } 249 return (res); 250 } 251 COMMAND_SET(copy_staging, "copy_staging", "copy staging", command_copy_staging); 252 #endif 253 254 static int 255 command_staging_slop(int argc, char *argv[]) 256 { 257 char *endp; 258 u_long new, prev; 259 int res; 260 261 res = CMD_OK; 262 if (argc > 2) { 263 res = CMD_ERROR; 264 } else if (argc == 2) { 265 new = strtoul(argv[1], &endp, 0); 266 if (*endp != '\0') { 267 printf("invalid slop value\n"); 268 res = CMD_ERROR; 269 } 270 if (res == CMD_OK && staging_slop != new) { 271 printf("changed slop, unloading kernel\n"); 272 unload(); 273 efi_copy_free(); 274 efi_copy_init(); 275 } 276 } else { 277 printf("staging slop %#lx\n", staging_slop); 278 } 279 return (res); 280 } 281 COMMAND_SET(staging_slop, "staging_slop", "set staging slop", 282 command_staging_slop); 283 284 #if defined(__amd64__) 285 /* 286 * The staging area must reside in the first 1GB or 4GB physical 287 * memory: see elf64_exec() in 288 * boot/efi/loader/arch/amd64/elf64_freebsd.c. 289 */ 290 static EFI_PHYSICAL_ADDRESS 291 get_staging_max(void) 292 { 293 EFI_PHYSICAL_ADDRESS res; 294 295 res = copy_staging == COPY_STAGING_ENABLE ? G(1) : G(4); 296 return (res); 297 } 298 #define EFI_ALLOC_METHOD AllocateMaxAddress 299 #else 300 #define EFI_ALLOC_METHOD AllocateAnyPages 301 #endif 302 303 int 304 efi_copy_init(void) 305 { 306 EFI_STATUS status; 307 unsigned long nr_pages; 308 vm_offset_t ess; 309 310 ess = EFI_STAGING_SIZE; 311 if (ess < DEFAULT_EFI_STAGING_SIZE) 312 ess = DEFAULT_EFI_STAGING_SIZE; 313 nr_pages = EFI_SIZE_TO_PAGES(M(1) * ess); 314 315 #if defined(__amd64__) 316 /* 317 * We'll decrease nr_pages, if it's too big. Currently we only 318 * apply this to FreeBSD VM running on Hyper-V. Why? Please see 319 * https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=211746#c28 320 */ 321 if (running_on_hyperv()) 322 efi_verify_staging_size(&nr_pages); 323 324 staging = get_staging_max(); 325 #endif 326 status = BS->AllocatePages(EFI_ALLOC_METHOD, EfiLoaderCode, 327 nr_pages, &staging); 328 if (EFI_ERROR(status)) { 329 printf("failed to allocate staging area: %lu\n", 330 EFI_ERROR_CODE(status)); 331 return (status); 332 } 333 staging_base = staging; 334 staging_end = staging + nr_pages * EFI_PAGE_SIZE; 335 336 #if EFI_STAGING_2M_ALIGN 337 /* 338 * Round the kernel load address to a 2MiB value. This is needed 339 * because the kernel builds a page table based on where it has 340 * been loaded in physical address space. As the kernel will use 341 * either a 1MiB or 2MiB page for this we need to make sure it 342 * is correctly aligned for both cases. 343 */ 344 staging = roundup2(staging, M(2)); 345 #endif 346 347 return (0); 348 } 349 350 static bool 351 efi_check_space(vm_offset_t end) 352 { 353 EFI_PHYSICAL_ADDRESS addr, new_base, new_staging; 354 EFI_STATUS status; 355 unsigned long nr_pages; 356 357 end = roundup2(end, EFI_PAGE_SIZE); 358 359 /* There is already enough space */ 360 if (end + staging_slop <= staging_end) 361 return (true); 362 363 if (!boot_services_active) { 364 if (end <= staging_end) 365 return (true); 366 panic("efi_check_space: cannot expand staging area " 367 "after boot services were exited\n"); 368 } 369 370 /* 371 * Add slop at the end: 372 * 1. amd64 kernel expects to do some very early allocations 373 * by carving out memory after kernend. Slop guarantees 374 * that it does not ovewrite anything useful. 375 * 2. It seems that initial calculation of the staging size 376 * could be somewhat smaller than actually copying in after 377 * boot services are exited. Slop avoids calling 378 * BS->AllocatePages() when it cannot work. 379 */ 380 end += staging_slop; 381 382 nr_pages = EFI_SIZE_TO_PAGES(end - staging_end); 383 #if defined(__amd64__) 384 /* 385 * amd64 needs all memory to be allocated under the 1G or 4G boundary. 386 */ 387 if (end > get_staging_max()) 388 goto before_staging; 389 #endif 390 391 /* Try to allocate more space after the previous allocation */ 392 addr = staging_end; 393 status = BS->AllocatePages(AllocateAddress, EfiLoaderCode, nr_pages, 394 &addr); 395 if (!EFI_ERROR(status)) { 396 staging_end = staging_end + nr_pages * EFI_PAGE_SIZE; 397 return (true); 398 } 399 400 before_staging: 401 /* Try allocating space before the previous allocation */ 402 if (staging < nr_pages * EFI_PAGE_SIZE) 403 goto expand; 404 addr = staging - nr_pages * EFI_PAGE_SIZE; 405 #if EFI_STAGING_2M_ALIGN 406 /* See efi_copy_init for why this is needed */ 407 addr = rounddown2(addr, M(2)); 408 #endif 409 nr_pages = EFI_SIZE_TO_PAGES(staging_base - addr); 410 status = BS->AllocatePages(AllocateAddress, EfiLoaderCode, nr_pages, 411 &addr); 412 if (!EFI_ERROR(status)) { 413 /* 414 * Move the old allocation and update the state so 415 * translation still works. 416 */ 417 staging_base = addr; 418 memmove((void *)(uintptr_t)staging_base, 419 (void *)(uintptr_t)staging, staging_end - staging); 420 stage_offset -= staging - staging_base; 421 staging = staging_base; 422 return (true); 423 } 424 425 expand: 426 nr_pages = EFI_SIZE_TO_PAGES(end - (vm_offset_t)staging); 427 #if EFI_STAGING_2M_ALIGN 428 nr_pages += M(2) / EFI_PAGE_SIZE; 429 #endif 430 #if defined(__amd64__) 431 new_base = get_staging_max(); 432 #endif 433 status = BS->AllocatePages(EFI_ALLOC_METHOD, EfiLoaderCode, 434 nr_pages, &new_base); 435 if (!EFI_ERROR(status)) { 436 #if EFI_STAGING_2M_ALIGN 437 new_staging = roundup2(new_base, M(2)); 438 #else 439 new_staging = new_base; 440 #endif 441 /* 442 * Move the old allocation and update the state so 443 * translation still works. 444 */ 445 memcpy((void *)(uintptr_t)new_staging, 446 (void *)(uintptr_t)staging, staging_end - staging); 447 BS->FreePages(staging_base, (staging_end - staging_base) / 448 EFI_PAGE_SIZE); 449 stage_offset -= staging - new_staging; 450 staging = new_staging; 451 staging_end = new_base + nr_pages * EFI_PAGE_SIZE; 452 staging_base = new_base; 453 return (true); 454 } 455 456 printf("efi_check_space: Unable to expand staging area\n"); 457 return (false); 458 } 459 460 void * 461 efi_translate(vm_offset_t ptr) 462 { 463 464 return ((void *)(ptr + stage_offset)); 465 } 466 467 ssize_t 468 efi_copyin(const void *src, vm_offset_t dest, const size_t len) 469 { 470 471 if (!stage_offset_set) { 472 stage_offset = (vm_offset_t)staging - dest; 473 stage_offset_set = true; 474 } 475 476 /* XXX: Callers do not check for failure. */ 477 if (!efi_check_space(dest + stage_offset + len)) { 478 errno = ENOMEM; 479 return (-1); 480 } 481 bcopy(src, (void *)(dest + stage_offset), len); 482 return (len); 483 } 484 485 ssize_t 486 efi_copyout(const vm_offset_t src, void *dest, const size_t len) 487 { 488 489 /* XXX: Callers do not check for failure. */ 490 if (src + stage_offset + len > staging_end) { 491 errno = ENOMEM; 492 return (-1); 493 } 494 bcopy((void *)(src + stage_offset), dest, len); 495 return (len); 496 } 497 498 ssize_t 499 efi_readin(readin_handle_t fd, vm_offset_t dest, const size_t len) 500 { 501 502 if (!stage_offset_set) { 503 stage_offset = (vm_offset_t)staging - dest; 504 stage_offset_set = true; 505 } 506 507 if (!efi_check_space(dest + stage_offset + len)) { 508 errno = ENOMEM; 509 return (-1); 510 } 511 return (VECTX_READ(fd, (void *)(dest + stage_offset), len)); 512 } 513 514 void 515 efi_copy_finish(void) 516 { 517 uint64_t *src, *dst, *last; 518 519 src = (uint64_t *)(uintptr_t)staging; 520 dst = (uint64_t *)(uintptr_t)(staging - stage_offset); 521 last = (uint64_t *)(uintptr_t)staging_end; 522 523 while (src < last) 524 *dst++ = *src++; 525 } 526 527 void 528 efi_copy_finish_nop(void) 529 { 530 } 531